Update documentation - using the transform() and doTransform() method on point clouds

[peci1]

On http://wiki.ros.org/tf2, there is no mention about the possibility of transforming and otherwise handling point clouds with tf2/tf2_ros/tf2_sensor_msgs.

I did a "survey" for my needs and collected what I found in http://answers.ros.org/question/11556/datatype-to-access-pointcloud2/?answer=215829#post-id-215829 . However, I can't say I understand it from such a "high-level" degree that I could write the tutorial myself...

There is also no tutorial on the client/server architecture.
And also tf2_sensor_msgs link is missing from the http://wiki.ros.org/tf2 top page "breadcrumb" with links to subordinate packages. But the page http://wiki.ros.org/tf2_sensor_msgs exists.
Finally, the page http://wiki.ros.org/tf2_eigen doesn't even exist.

Or did I search wrong?